This research is for continuance of the NSABP Group Operations Office, the Biostatistical Center, and Sub-contract support for non-grant-funded institutional members. The NSABP cooperative trials group was founded in 1958 and since 1970 has been headquartered at the University of Pittsburgh under the aegis of NCI Grant CA-12027, which in 1983 became a cooperative agreement. Included in this application are the elements of U10-CA-34211 and U10-CA-34212. These two cooperative agreements (formerly contracts) have been supporting NSABP breast and colo-rectal patient accrual since 1972 and 1977, respectively. Our long-range goal is to markedly improve the survival of patients with breast and colo-rectal cancers through more efficacious treatment strategies. Major specific aims for the upcoming five-year project period include: 1) complete accrual of on-going breast (B-13 thru B-17) colon (C- 02) and rectal (R-01) protocols; 2) continue long-term follow-up on all NSABP trials initiated since 1971 that have completed accrual; 3) update and continue follow-up on first generation breast protocols (B-01, B-02, B-03); 4) design and implement successor protocols; 5) initiate a protocol for locally advanced breast cancer; 6) extend quality control procedures to insure the integrity of treatments administered and validity of long-term therapeutic results; 7) continue the study of pathologic parameters; 8) assess tumor cell kinetics and receptors as predictive discriminants; and 9) initiate a male breast cancer registry. The NSABP has developed and implemented standardized methods and procedures across all protocols which include: 1) a thorough eligibility check at randomization of the large numbers of patients accrued through member institutions; 2) centralized review of pathology materials for all patients; 3) careful on-going toxicity monitoring to ensure identification and prevention of potential problems; 4)verification and editing of coded data with built-in quality assurance mechanisms; 5) detailed mechanisms that minimize delinquent data submission and ensure long-term follow-up reporting ; 6) medical audits of all active NSABP institutions at least once each three years; 7) regular reviews of institutional performance with respect to accrual compliance with protocol and data requirements and overall participation; 8) maintenance of appropriate administrative and fiscal records for institutions supported by subcontract; and 9) presentation of status for all protocols at semi-annual NSABP group meetings with publication of results in the literature.